The discoloration of pubic hair when you are pregnant may be a physiological phenomenon, or it may be a pathological phenomenon, such as hypothyroidism, vitiligo, malnutrition and other problems caused by. 1. Physiological phenomenon: the hormone level in the body will change after pregnancy, so there will be some physiological changes, such as pubic hair color change. 2. Pathological phenomenon: mainly due to diseases, such as hypothyroidism, vitiligo, malnutrition and so on. (1) Hypothyroidism: Hypothyroidism is mainly due to insufficient production or reduced action of thyroxine, patients may lead to thinning and discoloration of pubic hair. (2) Vitiligo: due to the destruction of melanocytes, so vitiligo patients may have hair color changes in the affected area. (3) malnutrition: when the lack of trace elements is caused by not malnutrition, female pubic hair discoloration after pregnancy can also occur. After pregnancy female pubic hair discoloration, should be timely to the hospital for further examination. After clarifying the cause of the disease, treatment will be carried out under the guidance of doctors.